NOVA
follows the fossil discovery and model recreation of the four-winged dinosaur,
Microraptor gui, and
investigates competing theories of how birds evolved.

The program:

profiles the Liaoning Province in northeastern
China, where the 130 million-year-old fossils were found.

notes that the first fossils of the feathered
dinosaurs turned up a decade ago.

explains how one researcher noticed that Archaeopteryx,
recognized since the 1860s as the earliest bird, looked
like a miniature version of Deinonychus,
a lightly built meat-eating dinosaur.

reviews the competing theories that flight
originated from the ground up with dinosaurs versus evolving from reptiles gliding
in the treetops.

presents research with chukkars (a type of bird) showing how they use their developing
wings to scramble up surfaces, a motion that later helps them fly.

shows how a scientific artist at the American
Museum of Natural History (AMNH) uses photos of more than 16 Microraptor specimens, analysis of scientific literature, and precise
measurements to sculpt a three-dimensional recreation of the Microraptorgui skeleton.

reports on efforts by scientists at the University
of Kansas to recreate a Microraptor by casting bones from a single specimen.

relates the Kansas group's hypothesis that
its model shows that Microraptor's hip joint could only allow a sprawling posture that
would not have been possible for dinosaurs, contrary to what the AMNH model
reveals.

documents the inspection of each
group's model by the other, and the continued confidence of each group in
its original hypothesis.

illustrates a model builder using the AMNH scientific reconstruction to create a
jointed model of Microraptor, complete with feathers.

details how scientists tested the model in
various wing positions in MIT's Wright Brothers Wind Tunnel, and reports
what they learned about the lift and drag forces generated in each position.

concludes by looking at Microraptor's position in the dinosaur family
tree, and notes that there will always be questions regarding how birds evolved
that cannot be answered with absolute certainty.

Taping Rights: Can be used up to one year after program is recorded off the air.